NCT06435429 · Jazz Pharmaceuticals
A Study Comparing the Efficacy and Safety of Zanidatamab to Trastuzumab, Each in Combination With Physician's Choice Chemotherapy, for the Treatment of Participants With Metastatic HER2-positive Breast Cancer
What this study is about
The effectiveness and safety of zanidatamab in combination with physician's choice of chemotherapy compared with trastuzumab in combination with physician's choice of chemotherapy will be evaluated for the treatment of participants with metastatic HER2-positive breast cancer who have progressed on, or are intolerant to, previous T-DXd treatment.
View original scientific description
The efficacy and safety of zanidatamab in combination with physician's choice of chemotherapy compared with trastuzumab in combination with physician's choice of chemotherapy will be evaluated for the treatment of participants with metastatic HER2-positive breast cancer who have progressed on, or are intolerant to, previous T-DXd treatment.
Interventions
DRUG
Zanidatamab
Administered by intravenous infusion
DRUG
Trastuzumab
Administered by intravenous infusion
DRUG
Eribulin
Administered by intravenous infusion
DRUG
Vinorelbine
Administered by intravenous infusion
DRUG
Gemcitabine
Administered by intravenous infusion
DRUG
Capecitabine
Given orally
Primary outcome measures
Progression-free Survival (PFS) Per RECIST Version 1.1 As Assessed by Blinded Independent Central Review (BICR)
Time frame: Until disease progression or death, up to approximately 44 months
PFS is defined as the time in months from randomization to the date of first documented disease progression (as assessed by BICR according to RECIST v1.1) or death from any cause, whichever occurs first.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Participants are eligible to be included in the study only if all of the following criteria apply: 1. Is 18 years of age or of the legal adult age per local standard at the time of signing the informed consent. 2. Has histologically confirmed HER2-positive breast cancer according to ASCO-CAP Guidelines as evaluated by a central laboratory 3. Participants with unresectable or metastatic HER2 positive breast cancer who have progressed on, or are intolerant to, previous T-DXd treatment. 4. Has measurable disease per RECIST version 1.1. 5. Is eligible to receive one of the chemotherapy options listed in the physician's choice of chemotherapy (eribulin, gemcitabine, vinorelbine, or capecitabine). 6. Participants with history of treated or clinically inactive CNS metastases are eligible as specified in the protocol. 7. Has a life expectancy of at least 6 months, in the opinion of the investigator. 8. Has adequate hematologic parameters as defined in the protocol. 9. Has adequate hepatic fun
Where
- Phoenix, Arizona
- Tucson, Arizona
- Cerritos, California
- Glendale, California
- Los Angeles, California
- San Francisco, California
- Aurora, Colorado
- Denver, Colorado
- Washington D.C., District of Columbia
- Fort Myers, Florida
- Jacksonville, Florida
- St. Petersburg, Florida
And 25 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Feb 10, 2026 · Source of record for eligibility and locations